CN101650610A - Optical touch pen and optical touch screen for mobile terminal - Google Patents

Abstract

The invention provides an optical touch pen for a mobile terminal, wherein the optical touch pen is provided with a fluorescent substance, and a part of light of an infrared light source is converted into visible light by using the fluorescent substance. The invention also provides an optical touch screen, when the optical touch pen is contacted with the optical touch screen, the optical touch pen converts a part of the infrared light source into visible light by using the fluorescent substance, and the optical touch screen detects the infrared light and the visible light to locate the contact position of the optical touch pen. By adopting the optical touch pen and the optical touch screen, part of light of the infrared light source can be converted into visible light by using the fluorescent substance, so that a user does not need to provide a power supply for the optical touch pen. In addition, an optical sensor or a camera built in the optical touch screen provides a faster implementation method for accurate positioning of the stylus.

Description

Optical stylus and optical touch screen for mobile terminal

technical field

The invention relates to a liquid crystal display screen of a mobile terminal, in particular to an accurate positioning technology of a liquid crystal display screen based on an optical touch pen.

Background technique

With the rapid development of mobile communication technology, more and more mobile phones provide more friendly human-computer interaction mechanisms, such as handwriting pads, touch screens, and stylus pens. When the user uses the handwriting tablet, it is faster than the key input method; when the user uses the stylus and the LCD screen with touch control function, he can quickly find the desired function menu and interface, eliminating the need to use keys The tedious process of searching for menus layer by layer. In addition, for mechanical buttons, the use of the stylus will not have any impact on the normal functions of the phone.

However, the stylus in the prior art also brings some troubles to users. For example, when a user logs in to the network, a local area on the display screen may contain a lot of information, and the positioning of the stylus is not very precise when exactly clicking on a certain piece of information. Additionally, current stylus typically provide a point light source at the tip to better target specific areas or specific points. However, the use of point lights will increase the power or battery.

Contents of the invention

Aiming at the above-mentioned defects in the precise positioning of the stylus in the prior art, the present invention provides an optical stylus and an optical touch screen for a mobile terminal.

According to one aspect of the present invention, an optical stylus for a mobile terminal is provided, wherein the optical stylus has a fluorescent substance, and uses the fluorescent substance to convert a part of light from an infrared light source into visible light.

Preferably, the infrared light source is an LED light source. Moreover, the light emitted by the LED light source is directly directed to the optical touch pen or propagates in the waveguide.

Preferably, the camera receives infrared light and visible light to locate the position of the optical stylus in the display area.

According to still another aspect of the present invention, there is provided an optical touch screen for a mobile terminal, wherein, when the optical stylus is in contact with the optical touch screen, the optical stylus uses a fluorescent substance to convert a part of the infrared light source into visible light, and then , the optical touch screen detects infrared light and visible light to locate the contact position of the optical stylus.

Preferably, the optical touch screen at least includes a first glass layer provided with a color filter, a second glass layer provided with a thin film transistor, liquid crystal molecules and an optical sensor. Further, an optical sensor is used to detect infrared light and visible light. Moreover, the light emitted by the infrared light source is directed to the optical touch pen or propagates in the first glass layer.

Preferably, the optical touch screen includes a waveguide and several cameras, and the light emitted by the infrared light source propagates in the waveguide.

Adopting the optical stylus of the present invention, the fluorescent substance coated on its surface can convert part of the light of the infrared light source into visible light, so the user does not need to provide power or batteries for the optical stylus, and the camera receives and detects the infrared light. Light and visible light can more accurately determine the specific location of the stylus click. In addition, the built-in optical sensor or camera in the optical touch screen of the present invention also provides a faster implementation method for the precise positioning of the stylus.

Description of drawings

Readers will have a clearer understanding of various aspects of the present invention after reading the detailed description of the present invention with reference to the accompanying drawings. in,

Fig. 1 shows a first embodiment of a stylus when using a camera-based optical touch screen according to an aspect of the present invention, wherein Fig. 1A shows a schematic diagram of an infrared LED light source emitting light to a camera, and Fig. 1B shows A schematic diagram of when the infrared LED light source emits light to the camera and encounters the stylus;

2 shows a second embodiment of a stylus when using an optical waveguide-based optical touch screen according to yet another aspect of the present invention;

FIG. 3 shows a first embodiment of an optical touch panel integrated with an embedded optical sensor according to yet another aspect of the present invention;

FIG. 4 shows a second embodiment of an optical touch panel integrating an embedded optical sensor according to yet another aspect of the present invention; and

Fig. 5 shows a schematic diagram of the control principle of the optical touch panel when an optical waveguide is used according to yet another aspect of the present invention.

Detailed ways

The specific implementation manners of the present invention will be described in further detail below with reference to the accompanying drawings.

Before describing multiple embodiments of the present invention with reference to the accompanying drawings, the principle of precise positioning based on optical touch technology will be briefly introduced. Optical touch technology is a technology different from the existing infrared, surface acoustic wave, resistive and capacitive touch principles, because the optical sensor responds quickly to subtle movements, making the user's application lighter, smoother and simpler. In addition, CCD optical touch technology has also broken the bottleneck of the original touch technology, greatly improving accuracy, response speed and lifespan. For example, two CCD cameras are installed on the top of the liquid crystal display screen of the user's mobile phone, which are respectively located in the upper left corner and the upper right corner. In addition, the CCD camera in the upper left corner emits light through the LED light, and enters the CCD camera in the upper right corner after being reflected by the surrounding reflective strips; similarly, the CCD camera in the upper right corner emits light through the LED light, and then enters the upper left corner after reflection in the CCD camera. In this way, the densely distributed light forms a light net in the touch area, and the space between the light reflected many times is within a small range (for example, 1mm). When a point is touched, the emitted light and the received light form an included angle, and at the same time, the CCD cameras at both ends form two included angles with the two rays and the line formed between the two cameras. According to the geometric principle, The exact coordinates of the touch point are entered by the controller, thereby realizing the touch response.

Figure 1 shows a first embodiment of a stylus when using a camera-based optical touch screen. Wherein, FIG. 1A shows a schematic diagram of an infrared LED light source emitting light to a camera, and FIG. 1B shows a schematic diagram of an infrared LED light source encountering a stylus when emitting light to a camera. Those skilled in the art should understand that the infrared LED light source in Figures 1A and 1B is just one of many types of light sources, but the object of the present invention is not limited thereto.

Referring to Figure 1B, when the stylus is in contact with the liquid crystal display, the stylus coated with a fluorescent substance on its surface converts the infrared rays emitted by the infrared LED light source into the wavelength range of visible light, that is to say, the stylus It is possible to convert one wavelength to another. At the contact point between the stylus and the liquid crystal display, the corresponding area on the liquid crystal display can be lighted by using the infrared light and the excited visible light. Those skilled in the art should understand that the coating of the fluorescent substance on the surface of the stylus is only an exemplary embodiment of the present invention, and the fluorescent substance can also be coated on other parts of the stylus.

FIG. 2 shows a second embodiment of a stylus for an optical touch screen based on an optical waveguide. In this embodiment, the infrared light emitted by the infrared LED light source is transmitted in the waveguide. Similarly, when the stylus is in contact with the touch screen, a part of the infrared light is converted into excited visible light by using the fluorescent substance on the surface of the stylus. During the whole process, the stylus does not need to provide its own power supply or battery, but realizes the lighting function through the excited visible light and the infrared light emitted by the infrared LED.

FIG. 3 shows a first embodiment of an optical touch panel integrated with an embedded optical sensor. As shown in Figure 3, in the optical touch panel, the upper layer is a glass layer with a color filter, and the lower layer is a glass layer with a thin film transistor, and a large number of liquid crystals are distributed between the color filter and the thin film transistor. molecular. In addition, when the light passes through the color filter and passes through the liquid crystal to the thin film transistor, the optical sensor detects the light. For example, optical sensors convert light signals into electrical current signals. Referring to FIG. 3 , when the infrared light emitted by the infrared LED encounters the stylus, the stylus coated with a fluorescent substance converts part of the infrared light into excited visible light. Next, another part of the infrared light and the excited visible light pass through the color filter and are detected by the embedded optical sensor. In other words, the optical sensor detects not only infrared light but also excited visible light. The display area clicked by the stylus is precisely positioned by comparing the conversion results of infrared light and visible light.

FIG. 4 shows a second embodiment of an optical touch panel integrated with an embedded optical sensor. 3 and 4, the upper layer of the optical touch panel is a glass layer with color filters, the lower layer is a glass layer with thin film transistors, and liquid crystal molecules are laid in the middle. However, in Figure 4, the light from the IR LED light source is only transmitted through the color filter glass layer. If the stylus does not touch anywhere in the display area, the infrared light travels in a straight line through the color filter glass layer. When the stylus touches the display area, part of the infrared light is reflected at the stylus, and part of the infrared light is converted into excited visible light by the fluorescent substance on the surface of the stylus. When part of the infrared light and the excited visible light pass through the color filter, they are detected by the optical sensor. For example, the optical sensor converts the infrared light into a first current signal, and the optical sensor converts the excited visible light into a second current signal. Generally, the first current signal is greater than the second current signal. By performing data processing on the converted current signal, the specific position where the stylus touches the display area can be precisely located.

Fig. 5 shows a schematic diagram of the control principle of the optical touch panel when the optical waveguide is used. As shown in FIG. 5 , when the infrared LED light source emits infrared light, at the position where the stylus touches the display area, the fluorescent substance on the surface of the stylus converts part of the infrared light into excited visible light. Those of ordinary skill in the art should understand that when part of the infrared light and the excited visible light pass through the waveguide and reach the camera, the camera can detect both the intensity of the infrared light and the intensity of the visible light. Using the light intensity comparison results between them, the specific position of the stylus can be precisely positioned.

Hereinbefore, specific embodiments of the present invention have been described with reference to the accompanying drawings. However, those skilled in the art can understand that without departing from the spirit and scope of the present invention, various changes and substitutions can be made to the specific embodiments of the present invention. These changes and substitutions all fall within the scope defined by the claims of the present invention.

Claims (10)

1. An optical stylus for a mobile terminal, characterized in that the optical stylus has a fluorescent substance by which a part of light of an infrared light source is converted into visible light.

2. The optical stylus of claim 1, wherein the infrared light source is an LED light source.

3. The optical stylus of claim 2, wherein light emitted by the LED light source is directed towards the optical stylus.

4. The optical stylus of claim 2, wherein light emitted by the LED light source propagates in the waveguide.

5. The optical stylus of claim 1, wherein a camera receives infrared light and visible light to locate a position of the optical stylus in a display area.

6. An optical touch screen for a mobile terminal, wherein when an optical touch pen is in contact with the optical touch screen, the optical touch pen converts a part of an infrared light source into visible light by using a fluorescent substance, and wherein the optical touch screen detects infrared light and visible light to locate a contact position of the optical touch pen.

7. The optical touch screen of claim 6, wherein the optical touch screen comprises at least a first glass layer provided with color filters, a second glass layer provided with thin film transistors, liquid crystal molecules, and optical sensors.

8. The optical touch screen of claim 7, wherein the optical sensor detects the infrared light and visible light.

9. The optical touch screen of claim 7, wherein light emitted by the infrared light source is directed toward the optical stylus or propagates within the first glass layer.

10. The optical touch screen of claim 6, wherein the optical touch screen comprises a waveguide and a plurality of cameras, and wherein the infrared light source emits light that propagates in the waveguide.

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